PBDB Timescale

International Chronostratigraphic Timescale

The interval definitions in this timescale are derived from the following sources:

K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view

There are 59 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 126844 collections

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International Chronostratigraphic Timescale			Devonian Subages	Ordovician of China			Carboniferous Subepochs
Carboniferous	Pennsylvanian	Gzhelian					Late Pennsylvanian	298.9
		Kasimovian					Late Pennsylvanian	303.7
		Moscovian					Middle Pennsylvanian	307
		Bashkirian					Early Pennsylvanian	315.2
	Mississippian	Serpukhovian					Late Mississippian	323.2
		Visean					Middle Mississippian	330.9
		Tournaisian					Early Mississippian	346.7
Devonian	Late Devonian	Famennian	Late Famennian					358.9
			Middle Famennian					365.3 *
			Early Famennian					368.5 *
		Frasnian	Late Frasnian					372.2
			Middle Frasnian					375.4 *
			Early Frasnian					379.3 *
	Middle Devonian	Givetian	Late Givetian					382.7
			Middle Givetian					383.7 *
			Early Givetian					385.9 *
		Eifelian	Late Eifelian					387.7
		Eifelian	Early Eifelian					390.3 *
	Early Devonian	Emsian	Late Emsian					393.3
		Emsian	Early Emsian					398.3 *
		Pragian	Pragian					407.6
		Lochkovian	Late Lochkovian					410.8
			Middle Lochkovian					412.8 *
			Early Lochkovian					415.6 *
Silurian	Pridoli							419.2
	Ludlow	Ludfordian						423
	Ludlow	Gorstian						425.6
	Wenlock	Homerian						427.4
	Wenlock	Sheinwoodian						430.5
	Llandovery	Telychian						433.4
		Aeronian						438.5
		Rhuddanian						440.8
Ordovician	Late Ordovician	Hirnantian		Hirnantian	Xiaoxita †/Shikou	Wufeng †		443.8
		Katian		Chientangkiangian		Wufeng †		445.2
		Katian		Neichianshanian/Hanjiang				449.5
		Sandbian		Neichianshanian/Hanjiang				453
	Middle Ordovician	Darriwilian		Darriwilian	Guniu †/Hulo			458.4
		Darriwilian		Darriwilian	Hunjiang †	Dawan †/Daobaowan/Ningkuo		466.3 *
		Dapingian		Dapingian				467.3
	Early Ordovician	Floian		Yiyangian				470
		Tremadocian		Xinchangian				477.7
		Tremadocian		Xinchangian		Lianghekou †		477.9 *
								485.4